The growth and properties of Ca_3TaGa_3Si_2O_(14) single crystals

摘要

We have successfully grown a new ordered langasite structure piezoelectric single crystal Ca_3TaGa_3Si_2O_(14) (CTGS) using the Czochralski (CZ) method. The single crystal structure was investigated by X-ray powder diffraction (XRPD) experiments and showed that the CTGS single crystals had a single phase and had the same structure as the La_3Ga_5SiO_(14) (LGS) crystal. The transmittance spectra from 190 to 3200 nm were measured and the transmittance of CTGS crystal was about 85% above 350 nm. The specific heat of the crystal has been measured to be 0.52 J/g K at room temperature. The thermal expansion coefficients perpendicular and parallel to Z direction has been measured to be 5.2 x 10~(-6) and 3.7 x 10~(-6)/K between 298.15 and 450 K by a thermomechanical analyzer (TMA).